TABLE OF CONTENTS The production of biofuels to replace oil and natural gas is in active development, focusing on the use of cheap organic matter (usually cellulose, agricultural, and sewage waste) in the efficient production of liquid and gas biofuels which yield high net energy gain. The carbon in biofuels was recently extracted from atmospheric carbon dioxide by growing plants, so burning it does not result in a net increase of carbon dioxide in the Earth s atmosphere. As a result, biofuels are seen by many as a way to reduce the amount of carbon dioxide released into the atmosphere by using them to replace nonrenewable sources of energy.
Gasoline is a blend of hydrocarbons with some contaminants, including sulfur, nitrogen, oxygen, and certain metals. Ethanol and methanol are biofuels that provide alternative to gasoline (Table 8.1). Bioethanol is a fuel produced by processing familiar and renewable crops such as cereals, sugar beet, and maize using natural fermentation. Blended with petrol at 10 percent, bioethanol can be used in vehicles without the need to change fuel or engine specifications.
| Fuel type | Available motor fuel |
|---|---|
| Traditional fuels | Diesel and gasoline |
| Oxygenated fuels | Ethanol, methanol, methyl tertiary butyl ether (MTBE), ethyl tertiary butyl ether (ETBE), tertiary butyl alcohol (TBA), and tertiary amyl methyl ether (TAME) |
| Alternative fuels | Liquefied petroleum gases (LPG), ethanol, 85% (E85); ethanol, 95% (E95); methanol, 85% (M85); methanol, neat (M100); compressed natural gas (CNG); liquefied natural gas (LNG); biodiesel (BD); hydrogen; and... |
